Honestly, part of the issue I have is this class is trying to emulate perhaps the most unique subclass in all of D&D. Subclasses are highly particular to setting, even if that setting is only implied. They are highly defined, which boost them with character and identity, but does ultimately limit their breadth. The D&D Monk is an early player's take on the historic Shaolin Monk. It introduced martial arts, a lot of non-casting magical abilities, and was one of the few resource-limited classes.

Being a monk is an ascetic lifestyle practiced by solitary seekers of spiritual wisdom. D&D's Shaolin-based monk is a mix of this focus on mysticism with the perfection of the body through ritual combat. The point of the class isn't to seek combat like a fighter, but rather enable personal inward exploration. Their interactions with others in the world could be practically unseen, openly giving, or even secretly destructive or pain inducing like the Scarlet Brotherhood.

Wizards have Traditions, Rogues Schemes, Fighters Fighting Styles, and Clerics Deities
The Martial Arts has Schools or Academies, but I would say they fall under Fighting Styles (it's in the name)
The Monks specialties are unlikely to be based on Deities, especially since the Shaolin were Buddhist.
Perhaps Teachings works? These could be by Monastery and Master.

Once we can get past emulating the highly specific D&D Monk we might be able to move on to a Monk class open to more variety.

Current Design

Spoiler:

1. Alignment Requirements. Wow! I'm guessing further advancement will be the sole drawback, but it's still shocking to see.

This class is quickly becoming exclusively about combat. Missing are percentile chance to kill an opponent and Quivering Palm, but also Evasion, Improved Evasion, Thief Abilities, Speak with Animals, Speak with Plants, Poison Immunity, Feign Death, and all of the Mental protections (vs. ESP, charms, Beguiling, Hypnosis, Suggestions, Telepathy, Mind Blast, Geas, and Quest), which I guess fall under Clear Mind. 3.x monks actually had even more with Timeless Body, Perfect Self and the like.

5. Monk Strictures - Other than Alignment there aren't any. Asceticism without treasure or magic item limits? Tithing to their monastery? Limits on hiring & mentoring? (hirelings & henchmen) Even limits on certain item use like flaming oil and poison?

6. With above, part of the cool part about monks is they were defined in the world. They couldn't be everything, but were unique to D&D. There were a limited number of monks in the world and beyond 7th level any Monk would have to engage in ritual combat with the Masters to advance. The old Monk is more of a subclass with a highly detailed religious order. There are many benefits and drawbacks. Characters should be able to break the strictures and face the consequences for doing so.

Mechanical critiques

Spoiler:

1. Expertise Dice - The biggest problem I see with expertise dice is their balancing mechanism. They are bonus damage in almost every single case and the game becomes finding out how to get this damage applied. Even simply reading the rules it's beginning to feel like how not to lose this benefit rather than creatively imagine how to be badass. It's a hard limit on usefulness in combat that's always known and never exceeded.

2. Maneuvers - No prerequisites? No higher level maneuvers? (Aren't these all just disguised Combat Feats?) I do like the layered effects, but shouldn't these be like Spells? ...that the default choice is the player creates their own or picks from their trainer's list.

3. Per Day Ki - Ki powers seem limited, but this seems reasonable. Healing is already tracked daily and stunning is a spell. However, if stunning were actually made into a at-will action coupled with any unarmed melee attack without a Maneuver, then Monks gain both a common defense against (most) foes and are a serious threat with the potential to kill with their fists. Quivering Palm is missing. I take it all 1-roll death threats are. In that case, simply make Stun a possible Sleep effect when using Ki.

Some Alternatives

Spoiler:

1. Include Specialities (Teachings / Masters)to enable players to shift the class's focus between mysticism and combat. This means they choose to more or less receive:

In return for more abilities the class is has no wealth, loses Ki abilities when in armor (any would), limited magic items (and fewer applicable), No Strength bonus on damage, no hirelings or henchmen until high level, and ritual combat to advance into the high levels.

These are the Teachings that leads to the perfection of the body in defense against the world. They are Mr. Hard to kill.

2. Include the possibility of Strictures that cause the class to lose some of its abilities, if ceased. The class could then be shifted into Fighter with some armor and advanced weapon training. Because Ki abilities are lost using implements as weapons and wearing armor would no longer be an issue.

Perhaps they could be required to meditate and physically stress themselves each day like Wizards push their intellects and clerics re-attune with their deity? This highly focused choreography is what is meant by Lawful (not simply following society's rules) and becomes pointless? ~lost if their Alignment shifts.

3. The game is losing its flavor due to predefined, well tread powers. They are becoming too uniform and predictable. Like almost every spell in the old Spell Compendium, Expertise Dice are beginning to feel like the fill in system holes. +Ac, +ability score roll, +hit points, +movement, and so on. Don't be afraid to create an entirely new game system just for a unique sub-class like this one. It doesn't need to be complicated and certainly not disconnected to everything else. Even leaving open the option for DMs to simply greater define powers like +AC for wooden armor or a bonus to saves just against dragons.

4. The most important note is, class features are about designing characters who take those classes to be highly functional in class-related situations. Now that may simply be what I see as a conversation another sees as a scientific test of their environment while another sees as fisticuffs. And then there's the guy who knows this is another assassination opportunity. Or the guy who will use it to perfect themselves. Monks powers are realizations of their journey along they way and openings into further exploration where most creatures could never go. They are self-focused, better in 1-on-1 situations and combats, but can aid a well balanced group quite well.

I have a question about Controlled fall maneuver. The fall damage is calculated how? I have not found among the documents playtest. Can someone help me? Otherwise, I guess I can use the traditional formula of the previous editions: Creature that fall take 1D6 points of damage per ten feet fallen, to a maximum of 20D6?

I am French. I therefore ask your indulgence if you do not always understood me clearly.